Transfer press



I VD'ezy 1930. F. 1". SHEEDY Er ALA 18,783,888

TRANSFER PRESS Filed March *'10, 1930 :am s

-//\/`ncwro/e5 FRAN/f T .sf/55D! f/UGH C, WooD A0 l.; 7WA UNG' ATTORNEYS.

Patented Dec. 2, 1930 I 'l g l UNITED STATES a .TRAUNQ CHARLEs r. TRAUNG,`

. AND rr. r. GARDNER PAU-Nr "OFFICE i FRANK.' r. saumur, ,Huarte Woon, ANn'LouisTRAuN'doFsAN YiigifNCrsco,f*CALI-y roiaNrA, `AssrrerNoias, :B Y DIRECT AND MEsNE- ASSIGNMENTS, 'ro THE riaAUNe Coivr- PANY, or sAN FRANCISCO, CALIroRNrA, A CCPA'RTNERSHIP C'oNsisrrNG'or 'Louis 4'JJRAivsFEnfranse Y n Application filed Marchio, i930;` serial` No]4.344516.,v

This'invention relates to presses used inv Y lithography and has for its objects'improvel ments in a transfer press whereby the use of a scraper and tympan are" avoided, the danger L of stretching the sheet metal printingplate is avoided, the plate is gaged from the leading edge asitfpasses through the'press in-,

stead of from the side, anabsolutely equalized pressure across the plate is had, the pressure Y 1o is automatically kicked of ,after passing the lplate through the press, and the pressure cannot bea'pplied until the bed is'in place.

. between'a pair of pressure rolls. Another object is the provision vof'a soft rubberlcovered pressure vroll in combinationwith `a fiat -reciprocating metal bed. Other objects will appear in the following description and ac` companying drawings. v

In the drawings Fig. 1 is a side elevation of our improved transfer press with the ends of the frame broken away and the bed broken so asto shorten the drawing. l v

Fig. 2'is a plan View of the leading or' for# ward'end' ofthe flat bed showing the spring actuated gages. I

Fig. 3 is an enlarged side view of the gage tripping mechanism as seen from the 'line 3 3 of Fig. 2.

Fig.` 4 is an enlarged detail of the lrelief valvefor breaking the pressure ofthe press. f lBefore describing our improvements, attention is called to the fact that in making lithographie transfers, such as transferring a lot of prints laid out on Ya keyboard to the prepared surface of a Vlarge sheet ofzinc'or aluminum7 that one notched end of the metal sheet 'is firstv aligned against stops or gages arranged along one sideedge of the flat iron bed of a press, the keyboard similarly notched and bearing the transfers is lowered face down upon the metal, the hinged tympan of the press is lowered, bed advanced under the scraper, the toggle lever lof the scraper is pulled down and the bed is passed under the scraper either by hand orpower.

The above practice subjects'the plate to ter,- riflc pressure concentrated across a narrow band and in spite of metal tympans being in common use, the sheet metal tympan as well as the printing plate lying on theflat Abed of n. iaYJACKsoN,4 wyaoHN's'roN, FRANK r. saumur? the press are" sometimes stretched to such` a degree as' to Vseriouslyt interfere with proper register in 4color jobs, but nevertheless,V the method asd'escribed is at the presentmoment in universal' use in the greatjlithograph houses ofthecountry. Inour' press we gage the plate from the' leading fedge indirection of travel through the transfer `press,something never done be-V fore, the tympan frame not permitting, and we apply the pressure bymeans ofa rubbercoveredroller Vforced down by means of an hydraulic pump', with a result that a better transfer is 4secured with f less pressure, no tympan is required, stretchingv of the plate is practically avoided but if it should take place toa slight extent sincethe gaging is at the leading edge instead of at the side as heretofore and the 'plate travelsthrough. the transferpressin the same direction as thro-ughthe cylinder presses it4 follows that any slight error due for. p "In the drawings one side lof the frame of the pressfonly is shown as it isunderstood that both? are alike tied by rods 2 and supporting between them the rollers and movable flat bed to str-etching is easily compensated 3 of the press;

The ilat bedis guided against lateral dis` placement and is supported, when not under pressure, on fidlers lcarried on the frame andJ whenv under 'pressure principally on a largev iron or steel roller 5, mounted in ,verti cally slidablebearings 6, and which rises up directly under'a similar roller coveredjwith a heavy layer of tough live rubber 8 vulcan- 12mounted` above and extendinginto'an oil reservoir 13A carried Non one `side frameV of thepress, the pressurepipe 1 4 fromft'he lower end of the pump coming up through the oil reservoir and leading acrossthe press to both pressure pistons as by vertical pipes 15, the one shown being for the forward bearing, while a return pipe 16 leads from the pressure pipe system back through a check valve 17 to the oil reservoir, it is of Course understood that the pump itself and oil reservoir are suitably check valved at their lower end in the well known way not detailed in the drawm pressure gage 18 is connected to the pressure line, and means is provided for automatically breaking the pressure at the endof the bed travel by opening check valve 17 in the return oil line to the reservoir and also for preventing the application of thehydrostatic pressure unless the lower roll 5 is in raised position under the bed as will be later explained.

Bed 3 is flat and as stated isnormally supported on idlers 4, but when pressure is applied by roll 8, the lower' roll 5 is elevated under the bed to just take its weight from the idlers and the revolving of the under roll under power applied through the train of gears 19, 20, 21, 22 from belt pulley 23 serves to draw the bed along between the rollers, pulley 23 being` any type of clutch pulley construction not detailed in the drawings.

When the traveling bed has carried the plate through the rollsand the hydraulic pressure has been broken, the lower roll is dropped and a short roll or wheel 24 carried on gear shaft 25 in verticallyslidable bearings 26 is raised to eontactf the under side of the bed and reverse its movement so as to return it to starting point. This is accomplished by supporting bearings 6 and 26 on both sides of the press on toggle levers 27, 28 connected by links 29, 30 for simultaneous action by means of a transversely extending shaft 31 provided at one side of the press with a hand lever 32, the arrangement being such that when the lever is pulled in one direction roll 5 will be elevated to Contact bottom of bed and wheel 24 will be dropped out of contact (as shown in Fig. l), and when pushed in the opposite direction the reverseposition will obtain so as to reverse the bed.

To hold the toggles just over the center their center pins work in slots 33, 34 in the frame so as to definitely limit their travel, toggles 27 are presumed to be justslightly over center so as to be locked against the hydraulic pressure roll above.

As it is important that the hydraulic pressure should not be capable of being applied unless lower roll 5 is elevated to supporting position we provide a release for relief valve 17 which holds it open when bearing 26 is raised, and consisting of an arm 35 secured at its lower end to the bearing 26 and with its upper end lying under a pin 36 projecting from a vertically movable rod 37 pivoted at its upper end to a lever 38 arranged to raise the valve stem 39 and open the valve when bearing 26 is raised.

Rod 37 also extends downward adjacent the side of the bed 3 and is lifted at the end of the bed travel by a wedge 40 carried by the bed so that the pressure will automatically be broken at end of travel, roll 8 will instantly rise under influence of springs 10 and the bed will be free to return.

The plate gages 41 at the forward edge of the bed are best shown in Figs. 2 and 3, and they comprise several Z-shaped lingers secured to. a transversely extending shaft 42 rotatably carried in ribs 43 of a pair of eX- tensions or ears 48 secured to or integrally extending from the forward edge of the bed 3.

Fingers or gages 41 are adapted to swing on shaft 42 from a. position lying in shallow recessesonthe'upper edge of the bed as shown in full lines in Fig. 3 for gaging the plate 53 and key-board 44,130 a forward released p0- siti on below the surface of the bed 3 as shown in dotted lines. Shaft 42' is actuated by spring 45 to automatically release the gage lingers -upon advancing the bed so that the upper roller will not be injured, and to this-end a latch 46 pivoted at 47 to one of the ears 48 engages a jaw 49 of a collar 50 `secured Vto shaft 42 to hold the gages over the bed, but allows them to fly forward when latch46 is raisedy by passing over a cam 51 carried on one of the frame tie rods 2.

n operation ofthe press the gage lingers are turned back to position by means of a small handle 52 on shaft 42.

Forwardly extending ears 48 are finished on the bottom coincident with the bottom of the bed and are for the purpose of giving the supporting roll 5 an advance frictional grip upon the bed for pulling it in, as well as a final grip for wheel or wheels 24 for pushing the bed back. It is of course evident that suitable bumpers or dash pots may be used at opposite ends of travel of bed as are commonl on all types of reciprocating flat bed presses.

We claim:

1. A transferpress comprising a frame, a flat bed reciprocable on said frame, a pressure roll extendingV across the upper face of said bed, a layer of tough resilient rubber on said roll, means for forcing said roll toward said bed, a supporting roll under said bed and under said pressure roll, means for lowering said supporting roll out of contact with said bed, a reversing roller under said bed and means for elevating the reversing roller to contact said bed, the means for lowering the supporting roll and elevating the .roller comprising vertically movable bearings for the roll and roller, toggle levers supported from the frame of the press arranged for moving the bearings up and down,

ISU

and operating linkage connecting the toggle levers.

2. A transferpress including a pair of side frames with al flat bed reciprocably mounted i ed thereon, a pressure roll eXtendingacross the press above the bed, and hydrostatic means for forcing said roll downward toward said bed comprising a pressure cylinder above each end of the roll, a force pump provided with piping leading to both cylinders, and a pressure relief valve on said piping tripped by the action of the press at a predetermined point of its operation.

4. A transfer press including a pair of side frames with a flat bed reciprocably mounted thereon, a pressure roll'extending across the press above the bed, hydrostatic means for forcing said roll downward toward said bed,

Y and means for releasing and rendering said hydrostatic means `ineifectlve upon the' return movement of said bed.

5. A transfer press including a pair of side frames with a iiat bed reciprocably mounted thereon, a pressure roll extending across the press above the bed, hydrostatic means for forcing said roll downward toward said bed, and means for releasing and rendering said hydrostatic means ineffective upon the return movement of said bed comprising a trip on the rear portion of the bed and mechanism operated by said trip during'its advance arranged for opening said valve.

6. A transfer press including a pair of side V frames with aflat bed reciprocably mounted thereon, a pressure roll extending across the ress above the bed, hydrostatic means for.

lorcing said roll downward towardl said bed, and means .for releasing and rendering said hydrostatic means ineffective upon the return movement of said bed, andmeans for automaticallyy liftingn said pressure roll. to

clear the bed upon release of thepressurcV per surface-of the bed as same advances vun-v der said roll.

9. In a transfer press of the character described, a pressure roll, aflat bed reciprocable under said roll, a plurality of gage lingers for swinging out of position'below the top ofthe bed, and means for automatically swinging said fingers out of position below' the upper surface of the bed as same ad vances under said roll 'comprising a spring tending to revolve said shaft torelease the A n fingers, a 'latch holding the shaft against-,the f action of said spring, and a striker on said press releasing said latch at a predetermined position of said bed. i

10. AV` transfer press including a pair ofl side frames, a pressure roll extending from frame to frame, a flat bed mounted for reciprocation under said pressure roll, a supporting drive roll under said bed adapted to contact said bed for driving thesame by friction in one direction, and means for reversing the direction of said bed.VV

11..,A transfer press including a pair of Vside frames, va pressure roll extending from 12. In a structure as specified in claim 11,

a forwardly extending ear on said bed adapt- Yed for frictional contact with the drive rolls.

FRANK T. SHEEDY. HUGH O. WOOD. LOUIS TRAUNG.

7 In a transfer press 'of the character de-` for swinging out of position below the top of the bed, and means for automatically swinging said ngers out of position below the up-v overlyingthe forward edge ofl said bed, a' 71057 shaft upon whichsaid fingers are mounted- 

